I found a lot of leaves tonight with the speckling. It was a pruning night anyways so I pruned almost all affected leaves from all the plants. Went a little apeshit with the Diatomaceous Earth and hit the area in and around the pots pretty hard, as well as lightly dusting lower fan leaves.
I'm still quite certain this is a pest issue but I haven't spotted anything directly yet.
@legalcanada I have actually had mites before (knock on wood) and long before I saw damage of this magnitude, I was able to spot the mites within a few minutes of searching. I've never had them to the point of making webs (knock on wood) because I usually catch them in early veg when I can go a little crazy with spraying. My plants are quite tall so I'm also able to get on my hands and knees and look up at them with the grow light shining through them and I see nothing. I've also not seen any eggs on the leaves I've chosen for exam under 60-120x magnfication.
My RH is always quite high too. During lights off with my door closed my RH gets upwards of 85% with temps of 19-20C. This may be slowing em down enough that its keeping their population so low it's harder to spot them (good thing I guess). The damage however is getting annoying, my plants are definitely not looking happy before or after their pruning.
I've read some info on Method-1 before. As far as I can tell the active ingredients are rosemary and peppermint oils. I've used peppermint oil before in the past with a combination of other stuff and had success but I was sure the Peppermint Oil caused burning of the plant. If this were something I could just make with Rosemary and Peppermint I'd definitely try it. Spraying 1/3rd of the way through flower in a room with already high humidity might not be wise either.
Going to sleep and hopefully tomorrow will look better, Thanks for the tips everyone.